RU2625917C2 - Method for improving highly loaded friction surfaces - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method of preparing the composition-modifier to using for the treatment of highly loaded metal friction surfaces of the friction pairs operating at the temperatures up to 250°C, which comprises administering a powder mixture of dispersed particles into a grease oil, stirring it and feeding the powder mixture stirred in the grease oil into the item. Said powder mixture comprises antigorite Mg₆Si₄O₁₀(OH)₈, lizardite Mg₃Si₂O₅(OH)₄ and chrysotile Mg₆Si₄O₁₀(OH)₈, and silicone oil is used as a grease oil, which is first solidified with PTFE micropowder to the desired consistency, and then said mixture is introduced into it. Said mixture contains the following component ratio, wt %: antigorite 2-10, lizardite 2-20, chrysotile 10-30 and polytetrafluoroethylene 25-60. The particles of the PTFE micropowder have the size from 1 to 5 microns. The particles size of antigorite, lizardite and chrysotile ranges from 200 to 400 nm.

EFFECT: duration of scheduled restoration works is increased, the costs of repair work are reduced, and the item work efficiency is increased due to reducing the friction coefficient, active counteraction to surface wear, increasing the critical load and welding load.

13 cl

Description

The invention relates to mechanical engineering, in particular to tribotechnics, and can be used in the processing of the working surfaces of machine parts operating under high loads, such as bearings of rolling mill rollers.

A known method for modifying the iron-containing surfaces of friction units No. 2201998 C2 of 06/29/2001, which consists in using a mixture of dispersed components of minerals in the form of alpha-chrysotile, orthochrysotile, tape lysardite and others to increase the wear resistance of the geometry of the friction surfaces.

However, with increased dynamic and temperature loads, this method is not effective.

The known method No. 2377340 C1 of 04/07/2008, which consists in using a mixture of chrysotile, chlorite and barite in a ratio of 0.5 / 0.4 / 0.1. The disadvantage of this method is the instability of the modifier solution due to the fractional composition, leading to precipitation and deterioration of the product, as well as low efficiency under high dynamic and temperature loads.

Closest to the claimed solution in technical essence and the achieved effect is method No. 2345176 C1 of 12.02.2008, which consists in using antigorite Mg ₆ Si ₄ O ₁₀ (OH) ₈ and lysardite Mg ₃ Si ₂ O ₅ (OH) ₄ with the addition of an oil base for the formation of anti-friction and wear-resistant coatings for components of machine parts and mechanisms. This method is taken as a prototype.

The disadvantages of this method are the low antifriction effect, the formation of abrasive particles as a result of the reactions of the iron-containing component of the composition, leading to abrasive wear, as well as low efficiency in highly loaded parts of machine parts.

The difference of the proposed method is the selection of the optimal fractional and functional composition of the mixture of minerals, which leads to a more pronounced antifriction effect, actively counteracts surface wear, increases the critical load and welding load.

Studies have shown that the addition of polytetrafluoroethylene powder to the prototype mixture increases the antifriction effect, actively counteracts surface wear, increases critical load and weld load. Therefore, the functional composition of the mixture is similar to that used in the prototype, however, it also includes a fraction of polytetrafluoroethylene, as well as chrysotile for the recovery effect.

Next, studies were conducted on the optimal fractional composition of the mixture, which showed the highest efficiency of antigorite, lysardite and chrysotile particles with a characteristic size of 200 to 400 nm and polytetrafluoroethylene particles with a characteristic size of 1 to 5 microns.

The following optimal weight ratio of components, wt. %: antigorite Mg ₆ Si ₄ O ₁₀ (OH) ₈ 2-10, lysardite Mg ₃ Si ₂ O ₅ (OH) ₄ 2-20, chrysotile 10-30 and polytetrafluoroethylene 25-60 for operating temperatures up to 250 degrees Celsius.

The use of a modifier is as follows. First, the base in the form of an organosilicon oil is thickened with micropowder of polytetrafluoroethylene to the consistency required by the final product. Next, a powder mixture is introduced from dispersed particles of antigorite Mg ₆ Si ₄ O ₁₀ (OH) ₈ , lysardite Mg ₃ Si ₂ O ₅ (OH) ₄ , chrysotile Mg ₆ Si ₄ O ₁₀ (OH) ₈ , stirring in it and feeding said powder mixture, mixed in grease, into the product.

The objectives and technical result of the proposed method are to increase the period of routine restoration work, reduce the cost of repair and restoration work and increase the efficiency of the product by reducing the friction coefficient, actively counteracting surface wear, increasing the critical load and welding load.

For example, when replacing the lubricant in the bearings of a medium-grade semi-continuous semi-continuous hot rolling mill of the 350th series with the claimed composition, the examination revealed a decrease in the wear of the treated friction pairs, as well as the instability of the machine, which indicates the efficiency of using this anti-friction recovery composition.

Claims (4)

1. The method of preparation of the modifier composition for use in the treatment of highly loaded metal surfaces of friction of friction pairs operating at temperatures up to 250 ° C, including the introduction of a powder mixture of dispersed particles into a grease, stirring in it and feeding the powder mixture mixed in a grease into the product characterized in that said powder mixture comprises antigorite Mg ₆ Si ₄ O ₁₀ (OH) ₈ , lysardite Mg ₃ Si ₂ O ₅ (OH) ₄ and chrysotile Mg ₆ Si ₄ O ₁₀ (OH) ₈ , and as a grease use organosilicon mass Lo, which is first thickened with micropowder of polytetrafluoroethylene to the desired consistency and then introduced into it the mixture, while the mixture contains the following ratio of components, wt. %: antigorite 2-10 lizardite 2-20 chrysotile 10-30 polytetrafluoroethylene 25-60 2. The method according to p. 1, characterized in that the particle size of the micropowder of polytetrafluoroethylene is from 1 to 5 microns. 3. The method according to p. 1, characterized in that the particle size of antigorite, lysardite and chrysotile is from 200 to 400 nm.